Quadcopters are beginning to play an important role in precision agriculture. In order to localize and operate the quadcopter automatically in complex agricultural settings, such as a greenhouse, a robust positioning system is needed. In previous research, we developed a spread spectrum sound-based local positioning system (SSSLPS) with a 20 mm accuracy within a 30 × 30 m greenhouse area. In this research, a noise tolerant SSSLPS was developed and evaluated. First, the acoustic noise spectrum emitted by the quadcopter was documented, and then the noise tolerance properties of SSSounds were examined and tested. This was done in a greenhouse with a fixed quadcopter (9.75 N thrust) with the positioning system mounted on it. The recorded quadcopter noise had a broadband noise compared to the SSSound. Taking these SSSound properties into account, the noise tolerance of the SSSLPS was improved, achieving a positioning accuracy of 23.2 mm and 31.6 mm accuracy within 12 × 6 m for both Time-division Multiple Access (TDMA) and Frequency-division Multiple Access (FDMA) modulation. The results demonstrate that the SSSLPS is an accurate, robust positioning system that is noise tolerant and can used for quadcopter operation even within a small greenhouse.

中文翻译：

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基于噪声的扩频声音本地定位系统，用于操作温室中的四轴飞行器。

四旋翼飞机在精密农业中开始发挥重要作用。为了在复杂的农业环境（例如温室）中自动定位并操作四轴飞行器，需要一个坚固的定位系统。在先前的研究中，我们在30×30 m的温室区域内开发了具有20 mm精度的基于扩频声音的本地定位系统（SSSLPS）。在这项研究中，开发并评估了抗噪声的SSSLPS。首先，记录了四轴飞行器发出的声噪声谱，然后检查和测试了SSSounds的噪声容忍特性。这是在带有固定四轴飞行器（推力为9.75 N）的温室中完成的，并安装了定位系统。与SSSound相比，记录的四旋翼飞机噪声具有宽带噪声。考虑到这些SSSound属性，SSSLPS的噪声容限得到了改善，对于时分多址（TDMA）和频分多址（FDMA）调制，定位精度分别在12×6 m内达到23.2 mm和31.6 mm。结果表明，SSSLPS是一种精确，强大的定位系统，具有耐噪声性能，即使在小型温室内也可以用于四轴飞行器操作。